Platt Pegmatite Mine, Big Creek pegmatite District, Carbon County, Wyoming, USAi
| Regional Level Types | |
|---|---|
| Platt Pegmatite Mine | Mine |
| Big Creek pegmatite District | Mining District |
| Carbon County | County |
| Wyoming | State |
| USA | Country |
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Latitude & Longitude (WGS84):
41° 6' 55'' North , 106° 30' 16'' West
Latitude & Longitude (decimal):
Type:
Köppen climate type:
Nearest Settlements:
| Place | Population | Distance |
|---|---|---|
| Encampment | 438 (2017) | 26.0km |
| Centennial | 270 (2011) | 36.5km |
| Saratoga | 1,677 (2017) | 45.4km |
| Walden | 584 (2017) | 46.5km |
Other/historical names associated with this locality:
Uranium King Mine; Platte mine
An Yttrium-enriched pegmatite mined for rare-earth elements by Mr. Ralph Platt in the 1950s. The original ore was considered to be Euxenite-(Y) but new information in 2002 indicates it is Samarskite-(Y). The classification scheme of Cerny and Ercit (2005) has the Platt Pegmatite in the Muscovite-REE, MSREL-REE class.
Platt’s Prospect is a pegmatite that produced 5,000 pounds (2.27 t) of Samarskite-(Y) concentrate in the 1950s. A brief note on the mine is in Harris and King (1987) and more extensively by Harris (2002) and Sutherland and Cola (2016). This is an unusual pegmatite due to the high enrichment in Y oxides. It produces the best Samarskite-(Y) crystals outside Madagascar and some of the few that are both unaltered and terminated. The pegmatite has not been weathered or altered, as all the Samarskite-(Y) samples on the internet have the same thin alteration with a metamict body. There were still plenty of small broken pieces of Samarskite to collect at the shaft dump in 2012 as there are photos in Mindat of collecting there and that there was no one in the vicinity.
Platt’s Prospect is a pegmatite that produced 5,000 pounds (2.27 t) of Samarskite-(Y) concentrate in the 1950s. A brief note on the mine is in Harris and King (1987) and more extensively by Harris (2002) and Sutherland and Cola (2016). This is an unusual pegmatite due to the high enrichment in Y oxides. It produces the best Samarskite-(Y) crystals outside Madagascar and some of the few that are both unaltered and terminated. The pegmatite has not been weathered or altered, as all the Samarskite-(Y) samples on the internet have the same thin alteration with a metamict body. There were still plenty of small broken pieces of Samarskite to collect at the shaft dump in 2012 as there are photos in Mindat of collecting there and that there was no one in the vicinity.
Select Mineral List Type
Standard Detailed Gallery Strunz Chemical ElementsCommodity List
This is a list of exploitable or exploited mineral commodities recorded at this locality.Mineral List
13 valid minerals.
Rock Types Recorded
Select Rock List Type
Alphabetical List Tree DiagramDetailed Mineral List:
| ⓘ Albite Formula: Na(AlSi3O8) Description: Albite (variety cleavelandite)
Columbite (excellent single crystals of columbite to 3 inches) |
| ⓘ Albite var. Cleavelandite Formula: Na(AlSi3O8) |
| ⓘ 'Allanite Group' Formula: (A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH) |
| ⓘ 'Biotite' Formula: K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 Description: Albite (variety cleavelandite)
Columbite (excellent single crystals of columbite to 3 inches) |
| ⓘ Cheralite Formula: CaTh(PO4)2 Description: Reportedly an alteration rind on Samarskite-Y. |
| ⓘ 'Cheralite-(Ce)' |
| ⓘ 'Columbite-(Fe)-Columbite-(Mn) Series' Description: Albite (variety cleavelandite)
Columbite (excellent single crystals of columbite to 3 inches) |
| ⓘ Epidote Formula: (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| ⓘ Euxenite-(Y) ? Formula: (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6 Description: Samples identified by EDS etc. as Samarskite-(Y) by Rasche and Jacobson (2023. |
| ⓘ 'Feldspar Group' |
| ⓘ 'Feldspar Group var. Perthite' |
| ⓘ Fluorite Formula: CaF2 Description: Albite (variety cleavelandite)
Columbite (excellent single crystals of columbite to 3 inches) |
| ⓘ 'Garnet Group' Formula: X3Z2(SiO4)3 |
| ⓘ Hematite Formula: Fe2O3 |
| ⓘ 'Limonite' |
| ⓘ Microcline Formula: K(AlSi3O8) |
| ⓘ Monazite-(Ce) Formula: Ce(PO4) References: Joan Rosell-Riba (2025)Identified by Joan Rosell: SEM-EDS |
| ⓘ 'Monazite Group' Formula: REE(PO4) Description: Albite (variety cleavelandite)
Columbite (excellent single crystals of columbite to 3 inches) |
| ⓘ Muscovite Formula: KAl2(AlSi3O10)(OH)2 Description: Albite (variety cleavelandite)
Columbite (excellent single crystals of columbite to 3 inches) |
| ⓘ Pyrolusite Formula: Mn4+O2 |
| ⓘ Quartz Formula: SiO2 Description: Albite (variety cleavelandite)
Columbite (excellent single crystals of columbite to 3 inches) |
| ⓘ Samarskite-(Y) Formula: YFe3+Nb2O8 Description: Originally called Euxinite but Harris (2002) has re-evaluated these crystals and called them Samarskite-(Y) instead of Euxenite-(Y). The samples have been identified by EDS etc. as Samarskite-(Y) by Rasche and Jacobson (2023)
The reddish-brown coating on the Samarskite has been identified in Mindat and E-rocks as Cheralite (Ca0.5Th0.5(PO4)). |
| ⓘ Schorl Formula: NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH) Description: Albite (variety cleavelandite)
Columbite (excellent single crystals of columbite to 3 inches) |
| ⓘ 'Tourmaline' Formula: AD3G6(T6O18)(BO3)3X3Z References: |
Gallery:
List of minerals arranged by Strunz 10th Edition classification
| Group 3 - Halides | |||
|---|---|---|---|
| ⓘ | Fluorite | 3.AB.25 | CaF2 |
| Group 4 - Oxides and Hydroxides | |||
| ⓘ | Hematite | 4.CB.05 | Fe2O3 |
| ⓘ | Quartz | 4.DA.05 | SiO2 |
| ⓘ | Pyrolusite | 4.DB.05 | Mn4+O2 |
| ⓘ | Samarskite-(Y) | 4.DB.25 | YFe3+Nb2O8 |
| ⓘ | Euxenite-(Y) ? | 4.DG.05 | (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6 |
| Group 8 - Phosphates, Arsenates and Vanadates | |||
| ⓘ | Monazite-(Ce) | 8.AD.50 | Ce(PO4) |
| ⓘ | Cheralite | 8.AD.50 | CaTh(PO4)2 |
| Group 9 - Silicates | |||
| ⓘ | Epidote | 9.BG.05a | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| ⓘ | Schorl | 9.CK.05 | NaFe2+3Al6(Si6O18)(BO3)3(OH)3(OH) |
| ⓘ | Muscovite | 9.EC.15 | KAl2(AlSi3O10)(OH)2 |
| ⓘ | Microcline | 9.FA.30 | K(AlSi3O8) |
| ⓘ | Albite | 9.FA.35 | Na(AlSi3O8) |
| ⓘ | var. Cleavelandite | 9.FA.35 | Na(AlSi3O8) |
| Unclassified | |||
| ⓘ | 'Biotite' | - | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
| ⓘ | 'Cheralite-(Ce)' | - | |
| ⓘ | 'Feldspar Group' | - | |
| ⓘ | 'Limonite' | - | |
| ⓘ | 'Monazite Group' | - | REE(PO4) |
| ⓘ | 'Tourmaline' | - | AD3G6(T6O18)(BO3)3X3Z |
| ⓘ | 'Feldspar Group var. Perthite' | - | |
| ⓘ | 'Columbite-(Fe)-Columbite-(Mn) Series' | - | |
| ⓘ | 'Garnet Group' | - | X3Z2(SiO4)3 |
| ⓘ | 'Allanite Group' | - | (A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH) |
List of minerals for each chemical element
| H | Hydrogen | |
|---|---|---|
| H | ⓘ Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
| H | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| H | ⓘ Muscovite | KAl2(AlSi3O10)(OH)2 |
| H | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| H | ⓘ Allanite Group | (A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH) |
| B | Boron | |
| B | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| B | ⓘ Tourmaline | AD3G6(T6O18)(BO3)3X3Z |
| O | Oxygen | |
| O | ⓘ Albite | Na(AlSi3O8) |
| O | ⓘ Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
| O | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| O | ⓘ Euxenite-(Y) | (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6 |
| O | ⓘ Hematite | Fe2O3 |
| O | ⓘ Microcline | K(AlSi3O8) |
| O | ⓘ Monazite Group | REE(PO4) |
| O | ⓘ Monazite-(Ce) | Ce(PO4) |
| O | ⓘ Muscovite | KAl2(AlSi3O10)(OH)2 |
| O | ⓘ Pyrolusite | Mn4+O2 |
| O | ⓘ Quartz | SiO2 |
| O | ⓘ Samarskite-(Y) | YFe3+Nb2O8 |
| O | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| O | ⓘ Tourmaline | AD3G6(T6O18)(BO3)3X3Z |
| O | ⓘ Cheralite | CaTh(PO4)2 |
| O | ⓘ Albite var. Cleavelandite | Na(AlSi3O8) |
| O | ⓘ Columbite-(Fe)-Columbite-(Mn) Series | |
| O | ⓘ Garnet Group | X3Z2(SiO4)3 |
| O | ⓘ Allanite Group | (A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH) |
| F | Fluorine | |
| F | ⓘ Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
| F | ⓘ Fluorite | CaF2 |
| Na | Sodium | |
| Na | ⓘ Albite | Na(AlSi3O8) |
| Na | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Na | ⓘ Albite var. Cleavelandite | Na(AlSi3O8) |
| Mg | Magnesium | |
| Mg | ⓘ Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
| Al | Aluminium | |
| Al | ⓘ Albite | Na(AlSi3O8) |
| Al | ⓘ Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
| Al | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Al | ⓘ Microcline | K(AlSi3O8) |
| Al | ⓘ Muscovite | KAl2(AlSi3O10)(OH)2 |
| Al | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Al | ⓘ Albite var. Cleavelandite | Na(AlSi3O8) |
| Si | Silicon | |
| Si | ⓘ Albite | Na(AlSi3O8) |
| Si | ⓘ Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
| Si | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Si | ⓘ Microcline | K(AlSi3O8) |
| Si | ⓘ Muscovite | KAl2(AlSi3O10)(OH)2 |
| Si | ⓘ Quartz | SiO2 |
| Si | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Si | ⓘ Albite var. Cleavelandite | Na(AlSi3O8) |
| Si | ⓘ Garnet Group | X3Z2(SiO4)3 |
| Si | ⓘ Allanite Group | (A12+REE3+)(M13+M23+M32+)O[Si2O7][SiO4](OH) |
| P | Phosphorus | |
| P | ⓘ Monazite Group | REE(PO4) |
| P | ⓘ Monazite-(Ce) | Ce(PO4) |
| P | ⓘ Cheralite | CaTh(PO4)2 |
| K | Potassium | |
| K | ⓘ Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
| K | ⓘ Microcline | K(AlSi3O8) |
| K | ⓘ Muscovite | KAl2(AlSi3O10)(OH)2 |
| Ca | Calcium | |
| Ca | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Ca | ⓘ Euxenite-(Y) | (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6 |
| Ca | ⓘ Fluorite | CaF2 |
| Ca | ⓘ Cheralite | CaTh(PO4)2 |
| Ti | Titanium | |
| Ti | ⓘ Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
| Ti | ⓘ Euxenite-(Y) | (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6 |
| Mn | Manganese | |
| Mn | ⓘ Pyrolusite | Mn4+O2 |
| Mn | ⓘ Columbite-(Fe)-Columbite-(Mn) Series | |
| Fe | Iron | |
| Fe | ⓘ Biotite | K(Fe2+/Mg)2(Al/Fe3+/Mg/Ti)([Si/Al/Fe]2Si2O10)(OH/F)2 |
| Fe | ⓘ Epidote | (CaCa)(AlAlFe3+)O[Si2O7][SiO4](OH) |
| Fe | ⓘ Hematite | Fe2O3 |
| Fe | ⓘ Samarskite-(Y) | YFe3+Nb2O8 |
| Fe | ⓘ Schorl | NaFe32+Al6(Si6O18)(BO3)3(OH)3(OH) |
| Fe | ⓘ Columbite-(Fe)-Columbite-(Mn) Series | |
| Y | Yttrium | |
| Y | ⓘ Euxenite-(Y) | (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6 |
| Y | ⓘ Samarskite-(Y) | YFe3+Nb2O8 |
| Nb | Niobium | |
| Nb | ⓘ Euxenite-(Y) | (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6 |
| Nb | ⓘ Samarskite-(Y) | YFe3+Nb2O8 |
| Nb | ⓘ Columbite-(Fe)-Columbite-(Mn) Series | |
| Ce | Cerium | |
| Ce | ⓘ Euxenite-(Y) | (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6 |
| Ce | ⓘ Monazite-(Ce) | Ce(PO4) |
| Ta | Tantalum | |
| Ta | ⓘ Euxenite-(Y) | (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6 |
| Th | Thorium | |
| Th | ⓘ Euxenite-(Y) | (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6 |
| Th | ⓘ Cheralite | CaTh(PO4)2 |
| U | Uranium | |
| U | ⓘ Euxenite-(Y) | (Y,Ca,Ce,U,Th)(Nb,Ta,Ti)2O6 |
Other Databases
| Link to USGS MRDS: | 10107762 |
|---|
Other Regions, Features and Areas containing this locality
North AmericaContinent
- Rocky MountainsMountain Range
North America PlateTectonic Plate
- Great Plains DomainDomain
- Southern Rocky MountainsOrogenic Belt
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Platt Pegmatite Mine, Big Creek pegmatite District, Carbon County, Wyoming, USA